This invention relates to a cam buckle for tightening the ends of a web or strap, and, more particularly, to a cam buckle with a sliding bar for pinching the web as the cam buckle is locked. The buckle may be provided with a second slot for webbing to pass through for securing the buckle and providing added safety.
The invention finds particular utility in releasably securing a scuba tank to a backpack, either soft or rigid, which is worn by a scuba diver. Scuba tanks are commonly secured by a strip of web-like material such as nylon belting. One end of the web is attached to a buckle, and the web is wrapped around the tank. The other end of the web is threaded through the buckle, and the tank is secured by closing the buckle to tighten the web about the tank. Some systems use four webs which are attached to a flexible wrap or backpack. Two of these webs hold buckles in fixed locations, and the other webs are passed through the buckles for attaching the scuba tank in a sling with two straps. This is known as a soft pack.
Conventional buckles generally require a complicated web-threading routine. If the web is not threaded properly, the tank can be lost. Also, when the buckle is unlocked to allow changing the tank, the position of the web often has to be readjusted before the buckle is locked again.
The invention provides an over-center cam buckle which greatly simplifies threading the web through the buckle. The buckle includes a pair of side walls and a first bar which extends between the side walls. A second bar is slidably mounted between the side walls adjacent the first bar. A loop is pivotally attached to the side walls rearwardly of the second bar. The buckle is pivotable about camming surfaces provided by the side walls between a locked position in which the pivotable attachment of the loop moves over center rearwardly of the second bar, and an unlocked position in which the pivotable attachment is above the second bar. One end of a web is secured to the loop, and the other end of the web is threaded around the second bar when the buckle is unlocked and secured to the web by hook and loop fasteners. When the buckle moves to the locked position, the second bar slides toward the first bar and pinches the web therebetween.